Suspend/Resume has stopped working

Suspending/Resume on my games have stopped working, everything is digital and there's been no outage either network or power wise.

Does the Xbox One need a static IP in order to have useful suspend/resume because network stuff will force it to drop a suspended game?

I've tried it with several games now (Horizon 2, Forza 6, Gears) and the result is the same. The suspended session is lost in a matter of hours, I'm also not in the preview program, so it can't have been a system update.